Browsing by Author "Hoepner, Paul H."

Now showing 1 - 6 of 6
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    Analysis of corn harvesting and grain handling systems in northeastern Virginia
    Burrowbridge, Donald Robert (Virginia Tech, 1965-06-09)
    Typical grain and combination grain and Livestock farms in Northeastern Virginia were selected for study of the available resources and their restrictions for harvesting, handling, drying and storing corn. The costs involved in various combinations of machinery and equipment for performing the above operations were analyzed and the proper combinations of resources under alternative resource and price conditions determined. A model for approximating the seasonal movement of prices was developed and used to predict the variability in the historical average price in the area. An enterprise budget was presented as an example for preparing budgets and estimates for specific farm situations with conditions similar to those existing in the ares of this study. Significant differences were found among the farms in the returns from the corn enterprise due to the time of sale, seasonal fluctuations in price, the quality and quantity of corn disposed, and the methods and resources used to harvest, dry, and store corn. It was found that the size of the operation, the resources available, risk and uncertainty, and timeliness must be considered in order to select a profit maximizing grain handling system.
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    An approach to considering uncertainty in developing long-term, least-cost wood procurement policies
    Haynes, Richard W. (Virginia Tech, 1968-12-15)
    An approach was developed to consider the uncertainty which is intrinsic to forestry decisions. The approach was termed a partial stochastic linear program because uncertainty was considered by introducing variation into one element of the linear programming model (the right hand side). To implement this approach, subjective evaluations were made, regarding the amount of uncertainty associated with the values in question. This approach was applied to a wood procurement problem which had been previously solved as deterministic. The previous problem was a case study of an integrated forest products firm with the objective of minimizing the present value of wood procurement over a 20-year study using linear programming. The management of this firm was required to make subjective estimates of the variation associated with each available source of supply. The original case study was then reformulated as a partial stochastic linear program. The solutions of the partial stochastic approach were compared to the deterministic solution. This comparison showed the procurement policies suggested by both approaches were much the same. However, the stochastic approach differed in that management could obtain information about the sensitivity of a policy or a source and establish trade-off relationships between the cost of one policy and the uncertainty of another policy. The questions of the extent of model building and the implications for future study in this area are also considered.
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    Economic corn production on congaree loam
    Lutz, J. H.; Jones, G. D.; Moody, John E.; Hoepner, Paul H. (Virginia Agricultural Experiment Station, 1964-07)
    Purpose of this experiment was to determine maximum economic production of corn on Congaree loam when best known cultural practices are followed
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    The effect of available resources on the forage-grain feeding ratios and forage production systems on selected Virginia grade A dairy farms
    Reynolds, Robert K. (Virginia Tech, 1962)
    Dairy farmers in Virginia are confronted with the problem of continually re-organizing and adjusting their farming operations in an effort to maintain or improve their competitive position. Increasing competition in dairying within the state, as well as potential competition developing in areas outside of the state, makes it essential that dairymen operate efficiently. In particular, they must give careful consideration to various ways of reducing their production costs. Feed costs make up 50 to 60 percent of the total cost of producing milk. Consequently, the feeding program on any dairy farm greatly affects the cost of producing milk and, ultimately, the net return to the farmer. This study had four objectives: (1) to determine the available resources and their restrictions on the farms included in this study; (2) to determine an optimum forage and grain production system and forage to grain feeding ratio for three levels of milk production per cow with milk sales at the blend price not to exceed the present total base sales; (3) to determine which of the three levels of milk production is the most profitable at the present blend price of $5.73 per 100 pounds; (4) to study the effect of changes in the price of milk on the relative profitability of the three levels of production per cow and the forage-to-grain feeding ratios when the amount of profitable milk production is less than the present base.
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    Estimated costs and returns for selected crop and livestock enterprises in the cash-grain area of northeastern Virginia
    Chambliss, R. Lee Jr.; Hoepner, Paul H. (Virginia Agricultural Experiment Station, 1964-05)
    Sample budgets for the input and output of farms
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    Monte Carlo Examination of Static and Dynamic Student t Regression Models
    Paczkowski, Remi (Virginia Tech, 1997-09-01)
    This dissertation examines a number of issues related to Static and Dynamic Student t Regression Models. The Static Student t Regression Model is derived and transformed to an operational form. The operational form is then examined in a series of Monte Carlo experiments. The model is judged based on its usefulness for estimation and testing and its ability to model the heteroskedastic conditional variance. It is also compared with the traditional Normal Linear Regression Model. Subsequently the analysis is broadened to a dynamic setup. The Student t Autoregressive Model is derived and a number of its operational forms are considered. Three forms are selected for a detailed examination in a series of Monte Carlo experiments. The models’ usefulness for estimation and testing is evaluated, as well as their ability to model the conditional variance. The models are also compared with the traditional Dynamic Linear Regression Model.